1. Field of the Invention
This invention relates to processes for the preparation of addition products and oligomers, and to the addition products and oligomers produced thereby.
2. Statement of Related Art
The dimerization of alkanoic acids having an .alpha.-carbon atom to the corresponding succinic acids using a manganese salt of the alkanoic acid as an oxidative coupling agent in the presence of the anhydride of the alkanoic acid is known from related patents U.S. Pat. Nos. 3,845,116; 3,875,224; and U.S. Pat. No. 3,927,077. It is also known from published German application no. 19 27 233 that the oxidative coupling of vinylacetic acid to 1,5-hexadiene-1,6-dicarboxylic acid can be carried out in the presence of manganese dioxide. Published German Application No. 19 33 693 discloses the preparation of succinic acid from acetic acid in a 5% yield by oxidative coupling in the presence of manganese (III) acetate.
In "Free Radical Additions to Esters of Unsaturated Fatty Acids. Preparation of Dicarboxylic Acids and Other Polyfunctional Products", The Journal of the American Oil Chemists' Society, Vol. 42, pages 457-461, a process is described for peroxide intitiated free radical addition of acetic acid, acetic anhydride, or ethyl cyanoacetate to methyl undecylenate or methyl oleate in which the reaction products were mainly monoaddition products, with small quantities of dimers, trimers, and higher telomers. See also U.S. Pat. No. 3,308,140 which relates to, inter alia, the addition of acetic anhydride to the double bond of an unsaturated fatty acid ester to provide, after hydrolysis, a dicarboxylic acid having two more carbon atoms than the parent fatty acid.
In G.B. 1,409,659 a method is disclosed whereby unsaturated neo-carboxylic acids are prepared from the reaction of olefins with carboxylic acids in the presence of a reducible transition metal compound such as a manganese compound in the presence of a carboxylic acid anhydride, and wherein the resulting unsaturated neo-carboxylic acid can be further reaction with a carboxylic acid in the presence of a manganese compound and a carboxylic acid anhydride.